Flooring blocks may be laid on the grounds of construction sites, storage sites for construction materials, car parking areas, parks, unpaved roads and sidewalks, and event sites such as squares, baseball fields, soccer grounds, and athletic track grounds (including in any case, natural grass, and artificial turf).
Conventional flooring blocks, for example, are disclosed in Japanese Published Unexamined Patent Application No. H11-152706. This flooring block is formed by symmetrically uniting two upper and lower plastic block members, and on the respective sides thereof, concave and convex engagement portions are formed, and at least along two facing sides parallel to each other, joint holes are formed, and by inserting a long joint member such as a joint pipe, rope, chain, or rod material through the joint holes, adjacent flooring blocks are joined to each other.
According to the flooring blocks described in this patent document, the flooring block consists of two upper and lower plastic block members joined to each other symmetrically, so that its manufacturing cost is high and assembly takes time. In addition, in the case of this flooring block, a number of flooring blocks are joined by a serial joint pipe or the like, and after the flooring blocks are joined, to replace a broken one, the serial joint pipe or the like which joins many flooring blocks must be pulled out and the flooring blocks must be all separated, so that the flooring block replacement is very troublesome.